Wednesday, July 09, 2025

SPACE/COSMOS

The Mars mission that could prep for a human landing




M-MATISSE_simulation 

video: 

A simulation of the M-MATISSE spacecraft, Henri and Marguerite, exploring the plasma environment around Mars.

view more 

Credit: M-MATISSE team







Royal Astronomical Society press release

9 July 2025

If we're to land humans on Mars in the coming decades, we'll have to know what challenges await them when they get there.

Enter M-MATISSE, a potential precursor to a crewed mission to the Red Planet which could use UK instrumentation being promoted at the Royal Astronomical Society's National Astronomy Meeting 2025 in Durham to revolutionise our understanding of space weather on Mars.

It would involve sending two robot orbiters to the fourth planet from the Sun to unravel the complex workings of the Martian magnetosphere (the region around a planet dominated by its magnetic field), ionosphere (a layer of ionized gas in the upper atmosphere) and thermosphere (where Mars loses its atmospheric gases to space), as well as the planet's lower atmosphere and radiation build-up.

This, researchers say, could help forecast potentially hazardous situations for spacecraft and astronauts, making it an essential precursor to any future robotic and human exploration.

It will also shed further light on the planet's habitability.

If the project gets the green light from the European Space Agency (ESA) next year, M-MATISSE would be the first mission solely dedicated to understanding planetary space weather at Mars.

Dr Beatriz Sánchez-Cano, of the University of Leicester, said: "M-MATISSE will provide the first global characterisation of the dynamics of the Martian system at all altitudes, to understand how the atmosphere dissipates the incoming energy from the solar wind, including radiation, as well as how different surface processes are affected by space weather activity.

"This is important because understanding the behaviour of the Martian system and the chain of processes that control space weather and space climate at Mars is essential for exploration.

"It leads to accurate space weather forecasts (i.e. accurate understanding of solar energy and particles at Mars) and, thus, prevents hazardous situations for spacecraft and humans on the Red Planet, as we well know from Earth space weather monitoring experience."

M-MATISSE, the 'Mars Magnetosphere ATmosphere Ionosphere and Space-weather SciencE', is one of the current three candidates in competition for ESA's next 'medium' mission. It is expected that one candidate mission will be chosen by mid-2026.

Solar Orbiter and Euclid are other examples of flying medium-class ESA missions, while Plato and Ariel are currently being built for launch in the next six years.

If selected, M-MATISSE would study Mars using two identical spacecraft, each carrying an identical set of instruments to observe the Red Planet simultaneously from two different locations in space.

One of the spacecraft, named Henri, would spend most of its time within the Martian plasma system, while the other called Marguerite is intended to mainly be in the solar wind and/or far tail of Mars, a largely unexplored region.

The mission could reveal how the solar wind influences Mars's atmosphere, ionosphere and magnetosphere. It also aims to investigate the impact of these interactions on Mars's lower atmosphere and surface, which is a key aspect to understand the Red Planet's habitability, as well as the evolution of its atmosphere and climate.

Dr Sánchez-Cano, winner of the RAS Fowler Award in 2022, added: "The UK is spearheading this large international effort during the mission selection phase.

"In particular, it is responsible for the particle instrument suite which will provide the most accurate to date observations of all particles at Mars, including neutrals, ions and electrons of different energies.

"It is also responsible for the mission Science Centre, where in coordination with the European Space Agency, the science of the mission will be planned and its data exploitation coordinated."

To find out more about the mission concept, visit: https://le.ac.uk/physics/research/space-projects-instrumentation/projects/m-matisse

ENDS


Images & video

M-MATISSE_simulation

Caption: A simulation of the M-MATISSE spacecraft, Henri and Marguerite, exploring the plasma environment around Mars.

Credit: M-MATISSE team

 

M-MATISSE mission trailer

Caption: The differing orbit configurations of the M-MATISSE spacecraft are revealed in this video, along with a flyby to Phobos and the field of view of their instruments.

Credit: European Space Agency

 

M-MATISSE spacecraft

Caption: A model of the M-MATISSE spacecraft.

Credit: Dr Beatriz Sánchez-Cano/European Space Agency


Further information

The talk 'The M-MATISSE mission: Mars Magnetosphere ATmosphere Ionosphere and Space weather SciencE. An ESA Medium class (M7) candidate in Phase-A.' will take place at NAM at 14:55 BST on Wednesday 9 July 2025 in room TLC101. Find out more at: https://conference.astro.dur.ac.uk/event/7/contributions/458/

If you would like a Zoom link and password to watch it online, please email press@ras.ac.uk

 

The UK would provide one of the payloads of the proposed M-MATISSE mission. It is responsible for the leadership of the Mars Ensemble of Particle Instruments (M-EPI), a set of particle instruments combined in a single unit with a common Data Processing Unit unique interface with the spacecraft.

One of these instruments is the Mars - Electron Analyser System (M-EAS), for in-situ detection of electrons on both M-MATISSE spacecraft. M-EPI measurement principle is to characterise the Martian particle environment at different energies, including atmospheric neutral particles, ionospheric ions, electrons and negative ions, magnetospheric ions and electrons, solar wind ions and electrons, and solar energetic particles.

 

Life on Venus? UK probe could reveal the answer



VERVE artist’s impression 

image: 

An artist’s impression of the proposed VERVE mission to Venus the answer whether tiny bacterial lifeforms really do exist in the planet’s clouds.

view more 

Credit: Danielle Futselaar






Royal Astronomical Society press release

9 July 2025

The answer to whether tiny bacterial lifeforms really do exist in the clouds of Venus could be revealed once-and-for-all by a UK-backed mission.

Over the past five years researchers have detected the presence of two potential biomarkers – the gases phosphine and ammonia – which on Earth can only be produced by biological activity and industrial processes.

Their existence in the Venusian clouds cannot easily be explained by known atmospheric or geological phenomena, so Cardiff University's Professor Jane Greaves and her team are plotting a way to get to the bottom of it.

Revealing a new mission concept at the Royal Astronomical Society's National Astronomy Meeting 2025 in Durham, they plan to search and map phosphine, ammonia, and other gases rich in hydrogen that shouldn't be on Venus.

This would involve building a CubeSat-sized probe with a budget of 50 million euros (£43 million) to hitch a ride with the European Space Agency's EnVision mission – scheduled for 2031. VERVE (the Venus Explorer for Reduced Vapours in the Environment) would then detach on arrival at Venus and carry out an independent survey, while EnVision probes the planet’s atmosphere, surface and interior.

"Our latest data has found more evidence of ammonia on Venus, with the potential for it to exist in the habitable parts of the planet's clouds," Professor Greaves said.

"There are no known chemical processes for the production of either ammonia or phosphine, so the only way to know for sure what is responsible for them is to go there.

"The hope is that we can establish whether the gases are abundant or in trace amounts, and whether their source is on the planetary surface, for example in the form of volcanic ejecta.

"Or whether there is something in the atmosphere, potentially microbes that are producing ammonia to neutralise the acid in the Venusian clouds."

Phosphine was first detected in the Venusian clouds in 2020 but the finding proved controversial because subsequent observations failed to replicate the discovery.

However, that didn't deter the team of researchers behind the JCMT-Venus project – a long term programme to study the molecular content of the atmosphere of Venus which first involved the James Clerk Maxwell Telescope in Hawaii.

They tracked the phosphine signature over time and found that its detection appeared to follow the planet's day-night cycle – i.e. it was destroyed by sunlight.

They also established that the abundance of the gas varied with time and position across Venus.

"This may explain some of the apparently contradictory studies and is not a surprise given that many other chemical species, like sulphur dioxide and water, have varying abundances, and may eventually give us clues to how phosphine is produced," said Dr Dave Clements, of Imperial College London, who is the leader of the JCMT-Venus project.

It was then revealed at last year’s National Astronomy Meeting in Hull that ammonia had also been tentatively detected on Venus. On Earth, this is primarily produced by biological activity and industrial processes.

But there are no known chemical processes or any atmospheric or geological phenomena which can explain its presence on Venus.

Although temperatures on the surface of the planet are around 450C, about 50km (31 miles) up it can range from 30C to 70C, with an atmospheric pressure similar to Earth's surface.

Under these conditions it would be just about possible for "extremophile" microbes to survive, potentially having remained in the Venusian clouds after emerging during the planet's more temperate past.

But the only way to know for sure, the JCMT-Venus researchers say, is to send a probe to find out.

New research papers about the latest discoveries are expected to be published later this year.

ENDS


The mission would involve building a CubeSat-sized probe with a budget of 50 million euros to hitch a ride with the European Space Agency’s EnVision mission. VERVE would then detach on arrival at Venus and carry out an independent survey.

Credit

Professor Jane Greaves


Images & captions

VERVE artist's impression

Caption: An artist's impression of the proposed VERVE mission to Venus the answer whether tiny bacterial lifeforms really do exist in the planet's clouds.

Credit: Danielle Futselaar

 

VERVE mission proposal

Caption: The mission would involve building a CubeSat-sized probe with a budget of 50 million euros to hitch a ride with the European Space Agency's EnVision mission. VERVE would then detach on arrival at Venus and carry out an independent survey.

Credit: Professor Jane Greaves


Further information

The talk 'VERVE - a proposal for an ESA mini-Fast mission to Venus' will take place at NAM at 17:25 BST on Wednesday 9 July 2025 in room TLC101. Find out more at: https://conference.astro.dur.ac.uk/event/7/contributions/462/

If you would like a Zoom link and password to watch it online, please email press@ras.ac.uk

 

JCMT-Venus is a long term programme to study the molecular content of the atmosphere of Venus. The team first used the James Clerk Maxwell Telescope (JCMT) in Hawaii to detect the phosphine on Venus.

Information on the detection can be found here: https://ras.ac.uk/news-and-press/news/hints-life-venus


Notes for editors

The NAM 2025 conference is principally sponsored by the Royal Astronomical Society and Durham University.

 

About the Royal Astronomical Society

The Royal Astronomical Society (RAS), founded in 1820, encourages and promotes the study of astronomy, solar-system science, geophysics and closely related branches of science.

The RAS organises scientific meetings, publishes international research and review journals, recognises outstanding achievements by the award of medals and prizes, maintains an extensive library, supports education through grants and outreach activities and represents UK astronomy nationally and internationally. Its more than 4,000 members (Fellows), a third based overseas, include scientific researchers in universities, observatories and laboratories as well as historians of astronomy and others.

The RAS accepts papers for its journals based on the principle of peer review, in which fellow experts on the editorial boards accept the paper as worth considering. The Society issues press releases based on a similar principle, but the organisations and scientists concerned have overall responsibility for their content.

Keep up with the RAS on InstagramBlueskyLinkedInFacebook and YouTube.

Download the RAS Supermassive podcast

 

About the Royal Astronomical Society

The Royal Astronomical Society (RAS), founded in 1820, encourages and promotes the study of astronomy, solar-system science, geophysics and closely related branches of science.

The RAS organises scientific meetings, publishes international research and review journals, recognises outstanding achievements by the award of medals and prizes, maintains an extensive library, supports education through grants and outreach activities and represents UK astronomy nationally and internationally. Its more than 4,000 members (Fellows), a third based overseas, include scientific researchers in universities, observatories and laboratories as well as historians of astronomy and others.

The RAS accepts papers for its journals based on the principle of peer review, in which fellow experts on the editorial boards accept the paper as worth considering. The Society issues press releases based on a similar principle, but the organisations and scientists concerned have overall responsibility for their content.

Keep up with the RAS on InstagramBlueskyLinkedInFacebook and YouTube.

Download the RAS Supermassive podcast

 

About the Science and Technology Facilities Council

The Science and Technology Facilities Council (STFC), part of UK Research and Innovation (UKRI), is the UK’s largest public funder of research into astronomy and astrophysics, particle and nuclear physics, and space science. We operate five national laboratories across the UK which, supported by a network of additional research facilities, increase our understanding of the world around us and develop innovative technologies in response to pressing scientific and societal issues. We also facilitate UK involvement in a number of international research activities including the ELT, CERN, the James Webb Space Telescope and the Square Kilometre Array Observatory.

linkedin.com/company/stfc

ukri.org/councils/stfc

 

About Durham University 

Durham University is a globally outstanding centre of teaching and research based in historic Durham City in the UK. 

We are a collegiate university committed to inspiring our people to do outstanding things at Durham and in the world. 

We conduct research that improves lives globally and we are ranked as a world top 100 university with an international reputation in research and education (QS World University Rankings 2026). 

We are a member of the Russell Group of leading research-intensive UK universities and we are consistently ranked as a top five university in national league tables (Times and Sunday Times Good University Guide and The Complete University Guide). 

For more information about Durham University visit: www.durham.ac.uk/about/

A model of the M-MATISSE spacecraft.

Credit

Dr Beatriz Sánchez-Cano/European Space Agency


Chang'e-6 samples unlock secrets of the Moon’s farside




Chinese Academy of Sciences Headquarters





The Moon's near and far sides exhibit striking asymmetry—from topography and crustal thickness to volcanic activity—yet the origins of these differences long puzzled scientists. China's Chang'e-6 mission, launched on May 3, 2024, changed this by returning 1,935.3 grams of material from the lunar farside's South Pole–Aitken Basin (SPA), the Moon's largest, deepest, and oldest known impact structure, measuring 2,500 kilometers in diameter. The samples arrived on Earth on June 25, 2024.

Previous studies indicated that the SPA was formed by a colossal impact approximately 4.25 billion years ago, releasing energy greater than that of a trillion atomic bombs. But the effect of this impact on lunar geology and thermal evolution was one of planetary science's greatest unsolved questions until recently.

In the past year, research teams led by CAS institutions including the Institute of Geology and Geophysics (IGG) and the National Astronomical Observatories (NAOC), along with Nanjing University and others, have made four landmark discoveries based on the SPA samples. Their findings were published in four cover articles in the journal Nature.

According to Prof. WU Fuyuan, a member of the Chinese Academy of Sciences and a researcher at IGG, the profound geological consequences of the impact that formed the SPA are, for the first time, revealed collectively in these four Nature papers.

The cover stories focus on the following areas:

Prolonged Volcanic Activity: Analysis identified two distinct volcanic phases on the lunar farside—4.2 billion and 2.8 billion years ago—indicating that volcanic activity persisted for at least 1.4 billion years, far longer than previously thought.

Fluctuating Magnetic Field: Measurements of paleomagnetic intensities in basalt clasts revealed a rebound in the Moon's magnetic field 2.8 billion years ago, suggesting that the lunar dynamo, which generates magnetic fields, fluctuated episodically rather than fading steadily.

Asymmetric Water Distribution: The farside mantle was found to have significantly lower water content than the nearside mantle, indicating that volatile elements are unevenly distributed within the lunar interior—adding another aspect to the Moon's asymmetry.

Mantle Depletion Signatures: Geochemical analysis of basalt points to an "ultra-depleted" mantle source, likely resulting from either a primordial depleted mantle or massive melt extraction triggered by large impacts. This highlights the role of major impacts in shaping the Moon's deep interior.

The first analysis of the samples was published by NAOC and its collaborators, detailing the samples' physical, mineralogical, and geochemical properties. The Guangzhou Institute of Geochemistry at CAS subsequently confirmed 2.8-billion-year-old farside volcanic activity, linking it to a highly depleted mantle. IGG, in turn, dated the SPA to 4.25 billion years ago, providing a critical reference point for studying early Solar System impacts.

These findings not only illuminate the evolution of the Moon's farside but also underscore the transformative impact of the Chang'e-6 mission, paving the way for deeper insights into planetary formation and evolution.

Mysterious ‘Dark Dwarfs’ may be hiding at the heart of the Milky Way





Durham University







A new kind of cosmic object could help solve one of the universe’s greatest mysteries: dark matter.

Particle Astrophysicists have proposed the existence of a strange new type of star-like object, called a ‘dark dwarf’, which may be quietly glowing in the centre of our galaxy.

Far from being dark in appearance, these unusual objects are powered by dark matter (the invisible substance thought to make up about a quarter of the universe).

The discovery comes from a UK-US research team and the full research findings has been published in the Journal of Cosmology and Astroparticle Physics (JCAP).

Using theoretical models, the scientists suggest that dark matter can get trapped inside young stars, producing enough energy to stop them from cooling and turning them into stable, long-lasting objects they call dark dwarfs.

Dark dwarfs are thought to form from brown dwarfs, which are often described as failed stars.

Brown dwarfs are too small to sustain the nuclear fusion that powers most stars, so they cool and fade over time. But if they sit in a dense pocket of dark matter, like near the Milky Way’s centre, they could capture dark matter particles.

If those particles then collide and destroy each other, they release energy keeping the dark dwarf glowing indefinitely.

The existence of these objects depends on dark matter being made of specific kinds of particles, known as WIMPs (Weakly Interacting Massive Particles).

These are heavy particles that barely interact with ordinary matter, but could annihilate with one another inside stars, providing the energy needed to keep a dark dwarf alive.

To tell dark dwarfs apart from other faint objects like brown dwarfs, the scientists point to a unique clue: lithium.

The researchers believe dark dwarfs would still contain a rare form of lithium called lithium-7.

In normal stars, lithium-7 gets burned up quickly. So, if they find an object that looks like a brown dwarf but still has lithium-7 that’s a strong hint it’s something different.

Study co-author Dr Djuna Croon of Durham University, said: “The discovery of dark dwarfs in the galactic centre would give us a unique insight into the particle nature of dark matter.”

The team believes that telescopes like the James Webb Space Telescope could already be capable of spotting dark dwarfs, especially when focusing on the centre of the galaxy.

Another approach might be to look at many similar objects and statistically determine whether some of them could be dark dwarfs.

Finding just one of these dark dwarfs, the researchers say, would be a major step towards uncovering the true nature of dark matter.

 

ENDS

 

Source

‘Dark Dwarfs: Dark Matter-Powered Sub-Stellar Objects Awaiting Discovery at the Galactic Center’, (2025), D. Croon, J. Sakstein, J. Smirnov and J. Sreeter, Journal of Cosmology and Astroparticle Physics (JCAP).

An embargoed copy of the paper is available from Durham University Communications Office. Please email communications.team@durham.ac.uk.

Graphics

Associated images are available via the following link: https://www.dropbox.com/scl/fo/q0wuo2s1zxt6seh7uyn2d/AIJ62MtF_L_hiIGT6o6XNPs?rlkey=eb1moqs5fzp37oz8zqaabmxbr&st=87kzrhj7&dl=0

About Durham University

Durham University is a globally outstanding centre of teaching and research based in historic Durham City in the UK.

We are a collegiate university committed to inspiring our people to do outstanding things at Durham and in the world.

We conduct research that improves lives globally and we are ranked as a world top 100 university with an international reputation in research and education (QS World University Rankings 2026).

We are a member of the Russell Group of leading research-intensive UK universities and we are consistently ranked as a top 10 university in national league tables (Times and Sunday Times Good University Guide, Guardian University Guide and The Complete University Guide).

For more information about Durham University visit: www.durham.ac.uk/about/

END OF MEDIA RELEASE – issued by Durham University Communications Office.

 

Popular teen movies reel back from visible signs of puberty



Many films offer problematic aspirations for young adults, study finds




Ohio State University





COLUMBUS, Ohio – Most popular coming-of-age movies don’t reflect the true challenges of adolescence, suggests new research. 

An analysis led by Kate Stewart, a PhD student in communication at The Ohio State University, found that films that feature teen protagonists tend to depict experiences incongruent to those that real-life adolescents face. Unlike a typical high school student, protagonists in movies, for example, are rarely shown to struggle with the physical aspects of puberty, and typically excel at initiating romantic relationships. 

These findings contribute to the idea that while on-screen representations of youth are vital touchstones, they emphasize largely unfamiliar and unattainable narratives, so that when young viewers compare their lives to what they see in media, they find they don’t measure up. 

Repeated exposure in the movies to idealized portrayals of romantic interaction and body image impacts how teens interact with the world around them, said Stewart.  

“In a perfect world we would see comforting, reassuring, informative depictions of these types of things,” she said. “But if you’re seeing certain depictions over and over again, then it’s going to start to affect how you view things and especially what you may come to expect.”

The study was recently published in the Journal of Children and Media

The researchers analyzed 53 popular films released between 2012 to 2021 such as Lady Bird, Percy Jackson: Sea of Monsters or The Fault in Our Stars, in which the main character was high school-aged. They coded key elements of puberty found in the movies. 

The main result was that these coming-of-age movies didn’t really include narratives about how real adolescents experience puberty. The large majority of movies exhibited a marked absence of physical puberty traits for both male and female characters, said Stewart.

Of the 53 main characters, both male and female, only two (3.8%) of them dealt with body hair. There were two characters (3.8%) dealing with acne. Among the 28 female leads, two characters dealt with breast development (7.1%) and four characters (14.3%) dealt with menstruation on screen. There were no characters who were depicted navigating growth spurts, changes in muscle development or voice changes. 

The study found that the actors portraying the main characters were typically older than high school students. The ages of the actors playing the lead roles ranged from 16 to 28 years old. Only 10 lead actors were actually high school-aged (14 to 18 years old) at the time of filming. 

And there is a lot of romance in these movies – much more than typically experienced by most adolescents, Stewart said. In most movies (88.7%), the main character had a clear love interest. Across all movies, there were 1,467 shared scenes between the main character and love interest. Of the 47 movies that had a love interest, 78.7% of them showed the main character having a successful romantic pursuit of their love interest.

Despite these choices, normalizing inauthentic experiences like easy romances and false body image expectations certainly isn’t something the movie industry is doing maliciously, said Stewart. 

“It’s kind of a weird disconnect and misalignment between those two big features of adolescence,” she said. 

This study suggests that movies don’t typically provide a realistic view of adolescence, instead offering an aspirational view. That’s not what young viewers want, according to a 2024 report by the Center for Scholars and Storytellers.

It found that many teens are steering away from romance in the movies, as 63.5% of adolescents expressed a preference for stories focused on friendships and platonic relationships, rather than romance unnecessary to advancing the plot. 

In other words, movies dealing with real-world issues with models whose lives are more relatable would be powerful tools for teens navigating extreme developmental changes.

Researchers add that the work serves as a stepping stone to understanding how other types of social norms impact young people’s feelings toward relationships and body image. 

“Our hope is that the industry will begin to weigh those pros and cons of allowing teen audiences to see puberty and more realistic changes,” said Stewart. “By shining a spotlight on this, we’re hoping to move forward and build on what we know about what teens learn from media.” 

Nicole Martins of Indiana University was a co-author. 

#

Contact: Kate Stewart, Stewart.2337@osu.edu

Written by: Tatyana Woodall, Woodall.52@osu.edu

 

Kinsey Institute study shows sexual pleasure remains important for women across menopause transition




Kinsey Institute






Although there is a lot of discussion around negative aspects of aging and sexual problems, a new nationally representative study of 1,500 U.S. women aged 40-65 reveals that despite reporting masturbating less often, most post-menopausal women continue to experience orgasm at the same frequency and quality as their younger peers.

The study, conducted by researchers at the Kinsey Institute and published in Menopause, is among the first to examine masturbation, orgasm quality, and sex toy use across different stages of the menopause transition (pre-, peri-, and post-menopause). The findings offer several clinical and industry insights and suggest that promoting masturbation among older women may have several positive outcomes.

Key findings:

  • Orgasm frequency during masturbation doesn't change with age, with most women reporting they reach orgasm 81% of the time on average regardless of menopause transition stage
  • Peri- and post-menopausal women were more likely to say the quality of their orgasms improved rather than worsened in the last 10 years
  • The percentage of time that sex toys were used during masturbation was very similar across the 3 groups, ranging from 41% to 47% with the most common types of sex toys being wand vibrators and rabbit vibrators
  • Postmenopausal women were significantly less likely to have masturbated compared with both the premenopausal and perimenopausal groups, and rated the importance of masturbation in their lives slightly lower (3.5 vs. 4.2 on a 7-point scale)

These findings have several important clinical implications. Firstly, they underline the fact that many postmenopausal women continue to engage in self-stimulation, which previous research suggests can enhance well-being and ameliorate some menopausal symptoms. Secondly, underscore the need for health professionals to discuss the health benefits that masturbation can bring for older women. they indicate sex toys are becoming more acceptable in recent years although self-stimulation may still be considered taboo, especially for women in relationships. For industry manufacturers, the results indicate the importance of designing sex toys specifically for older women to make self-pleasure more accessible.

 

Live well temperature variations stress out largemouth bass, study finds




University of Illinois College of Agricultural, Consumer and Environmental Sciences
Allison Hay with largemouth bass 

image: 

Illinois researchers, including Allison Hay (pictured), aimed to improve fish health in live wells during angling tournaments. They found that live well temperatures change drastically throughout tournaments, particularly if anglers add ice, stressing fish.

view more 

Credit: University of Illinois Urbana-Champaign





URBANA, Ill. -- If you’ve ever been on a fishing boat, you might be familiar with live wells – small water tanks, built into the boat, where live fish can be stored. In bass fishing tournaments, these live wells keep fish alive throughout the competition, so that they can be released at the end. Anglers are always looking for ways to keep fish safe and healthy in these wells, since live bass mean higher prizes and more fish spawned for next year.

Researchers at U. of I. studied the effect of live well temperature variation on largemouth bass health and recovery time during tournaments, and shared their results in the North American Journal of Fisheries Management

Cory Suski, professor of natural resources and environmental sciences, part of the College of Agricultural, Consumer and Environmental Sciences, and his former master’s student, Allison Hay, found that live well temperatures are highly variable, in part due to angler’s activities during tournaments. Temperature variations can negatively impact bass’ activity upon release, they discovered.

The largemouth bass angling landscape 

Previous studies have found that tournaments can be deadly for captured fish, with mortality rates approaching up to 43% in some events, particularly in warm summer months. Because around 32,000 angling events take place across North America annually, minimizing mortality is crucial to ensure fisheries stay healthy and usable for decades to come. 

“Angling itself is pretty benign,” Suski said. “But live wells are the longest point of contact between the angler and the fish. So the anglers have a lot of potential to influence the fish during that period.”

Unfavorable live well conditions, such as low oxygen and crowding, pose physiological challenges to individual fish and stress a population that is caught and released repeatedly across multiple tournaments. Because largemouth bass are the most popular target for tournament anglers, improving outcomes for them could have major conservation implications. 

The study was developed in coordination with the Illinois Department of Natural Resources. Because state entities are responsible for enforcing fishing regulations, their relationship with anglers can become strained, Hay said. “I came in as the third party, and I noticed there was a lot of variation in practices across these anglers, just by having conversations with them.”

Forging connections with anglers

Anglers are motivated to keep their fish in good health, both out of love for the animal and the sport, and because points are deducted when fish die. Some anglers use ice to cool down their live wells, thinking that this will benefit the fish. Newer bass boats have recirculators, which pump in water from outside the boat. This means temperatures in a live well might oscillate throughout a tournament, causing fish physiological stress. “It’s like being in the shower and someone flushes the toilet,” Suski said. Stressed fish have longer recovery times, and need more time to resume normal activities once released.

But research on these methods is lacking, the scientists said. “The angling community puts a lot of stock in word of mouth – what they hear from people in their community, maybe on social media, maybe just their friends at the bar,” Hay said. “So if we have these false narratives of what’s good for a fish, that can be really detrimental and exacerbate a problem they didn’t know was happening.” 

By interacting directly with anglers during tournaments, Hay and Suski could find out what was actually happening, and figure out whether methods could be improved.

To this end, the researchers’ first step was to collect live well temperature data during four 2023 tournaments at Clinton Lake, in Dewitt County, Illinois. This meant showing up to tournaments, building relationships, and gaining the anglers’ trust.

“I grew up in the middle of nowhere, East Texas, so there's a little bit of an overlap in the culture, and I felt like I could relate to the anglers a little bit more,” Hay said.

“Ninety-nine percent of the study was Allison's relationship building,” Suski said. “One percent of it was the technology just changed.” While anglers might be hesitant to allow scientists to put cumbersome equipment on their boats, they didn’t mind the team’s new, unobtrusive temperature sensors, the size of a few stacked quarters.

Understanding live well conditions

In the lab, Hay and Suski conducted simulations of the conditions they noted at tournaments, exposing largemouth bass to temperature variations and other stressors, such as exercise. To quantify the impact of temperature changes on the fish, the researchers assessed their reflexes and analyzed the animals’ blood for indicators of physiological damage.

The team found that live well temperatures changed drastically throughout tournaments, particularly if anglers added ice during the fishing day, and that this had a negative impact on largemouth bass. While no fish in the study died and their reflexes were not impaired, temperature oscillations exceeding 5 degrees Celsius (around 7 degrees Fahrenheit), generated physiological stress as indicated by blood analysis. 

Making evidence-based practices accessible

Hay and Suski recommend that anglers refrain from adding ice to their live wells, and instead encourage them to aim for consistent temperatures, as close to surface water temperatures as possible. 

Suski continues to research bass health during angling tournaments, and the researchers hope to make evidence-based angling recommendations more widely accessible. They continue to work on sharing their results widely amongst anglers and fisheries managers, such as the Department of Natural Resources.

Hay hopes that this study will encourage communication between anglers, managers, and scientists. “They love fish, and I love fish,” Hay said. “So I really wanted to emphasize that I'm not there to take this resource away from them. I'm there to make sure this resource is here for them and their kids and their grandkids.”

The study, “Quantifying the impact of temperature variation in live wells on Largemouth Bass,” is published in the North American Journal of Fisheries Management [DOI:10.1093/najfmt/vqaf016]. Authors include Allison Hay, Jackson Glomb, Reagan Oller, and Cory Suski.

The research was supported by the Federal Aid in Sport Fish Restoration Program via the U.S. Fish and Wildlife Service administered by the Illinois Department of Natural Resources, project 391-F-202-R-4, along with US Department of Agriculture National Institute of Food and Agriculture Hatch Project ILLU-875-940- awarded to Cory Suski, an Illinois Muskie Tournament Trail Research Grant awarded to Allison Hay, an Illinois American Fisheries Society Student Research Award awarded to Allison Hay, and Natural Resources and Environmental Sciences HATCH Summer Internship Program awarded to Reagan Oller.

Cory Suski is also affiliated with the Institute for Sustainability, Energy, and Environment, the Prairie Research Institute, and the Center for Latin American and Caribbean Studies.